The present invention relates to a folding container comprising side walls disposed in a fashion surrounding a bottom portion of the container and which can be folded so as to overlap the bottom portion.
By way of example, a folding container is conventionally known which comprises long side walls connected via a hinge section to opposed long side portions of a bottom portion of the container formed to have a generally rectangular planar shape and short side walls connected also via a hinge section to opposed short side portions of the bottom portion.
This folding container is configured as follows: to fold the container, the short side walls are folded so as to overlap the bottom portion, and the long side walls are further folded onto the short side walls. Then, to erect the container the folded long side walls are stood up perpendicularly with respect to the bottom portion, and folded short side walls are then stood up perpendicularly with respect to the bottom portion to thereby assemble the box-shaped folder container.
When the folding container is folded, the bottom portion is located at the bottom, the short side walls, which are folded so as to overlap the bottom portion, are located thereof, and the long side walls, which are folded so as to overlap the short side walls, are located thereon. To stack up folding containers folded in this matter, the bottom portion of an upper folded folding container is placed on the long side walls of a lower folded folding container, in addition, the folding container has generally L-shaped fitted shoulder sections, each formed near a corresponding one of the lower corners (located on the bottom portion side) of the long side walls thereof, so that when tile container is folded, the fitted shoulder sections, each having a generally L-shaped planar shape, are each located at a corresponding one of the four corners of the two long side walls. Since the folding container is configured so that in stacking up folded folding containers, the bottom portion of an upper folded folding container is fitted in the shoulder sections located-at the four corners of the two long sidewalls of a lower folded folding container, horizontal movement of the upper folded folding container relative to the lower folded folding container is limited to allow a large number of folded folding containers to be stacked up stably to prevent collapse.
As described above, in the conventional folding container, the fitted shoulder sections are each formed near the corresponding one of the lower corners of the long side walls of the folding container so as to stably stack up folded folding containers. In the assembled folding container, however, the fitted shoulder sections project from the long side walls. Consequently, if two assembled folding containers are arranged in juxtaposition in a manner such that the long side walls of one of the containers abut on the corresponding long side walls of the other, an unwanted gap is created between the folding containers arranged in juxtaposition to increase a storage space for the assembled folding containers, thereby reducing storage efficiency. In addition, the fitted shoulder sections disadvantageously increase the thickness of each long side wall, so that the assembled folding container has a small internal volume compared to its outside dimensions, resulting in a reduced accommodation efficiency.
Additionally, since the long side walls insufficiently engage with the short side walls when the conventional folding container is assembled, the long and short side walls may be mutually disengaged when a load is imposed on these side walls from above, for example, when the assembled folding containers are stacked up.
Further, when a load is imposed on the long and short side walls of the conventional folding container from above, this load is effected on the hinge section coupling the bottom portion to the long and short side walls, whereby the hinge section may be damaged.
Further, since the conventional folding container has a problem with the structure of the hinge section coupling the bottom portion to the long and short side walls, it cannot be assembled easily by hinging the bottom portion to the long and short side walls.
Additionally, card holders disposed on the conventional folding container are manufactured separately from the other components before being attached to the long or short side walls. This attachment requires a large amount of time and labor to increase the price of the folding container.
It is an object of the present invention to solve the above described problems with the conventional folding container to provide a folding container that can be handled more easily and accommodated more efficiently.
To attain this object, the present invention is a folding container comprising side walls disposed in a fashion surrounding a bottom portion thereof and which can be folded so as to overlap the bottom portion, the side walls each having engagement frame sections formed thereon for mutually engaging the adjacent side walls so that when stood up perpendicularly to the bottom portion, the side walls will not fall down inward. In this folding container, first, the bottom portion has locking blocks formed thereon and on which the bottom portion of an assembled folding container can be fitted, the side walls each have recesses formed therein and each having an open underside into which the corresponding engagement block of an assembled folding container can be inserted, and the engagement frame sections are used to mutually engage the side walls and to engage the side walls with the bottom portion. Second, one of the opposed side walls has through-holes into which the corresponding engagement block, which projects upward, can be inserted upon folding. Third, engagement projections formed on the engagement frame sections of each side wall are configured to fit in the corresponding through-hole in each fitting section formed in the bottom portion. Fourth, when the side walls are stood up perpendicularly to the bottom portion, a bottom surface of each side wall partly comes in surface contact with a top surface of the bottom portion. Fifth, card presser pieces each constituting a card holder are integrated with the side wall via a thin connection section.